Motor-cycle-speed-indicator drive connection.



APLICATION FILED FEBZS, 1910.

Patented June 27, 19H.

SWMMMWWM Parar-ir onirica.

JOHN KERWIN STEWART, OF CHICAGO, ILLINOIS.

Specification of Letters Patent.

MOTOR-CYCLE-SPEED-INDICATOR DRIVE CONNECTION.

Patented June 27, 1.911'.

Application led February 25, 1910. Serial No. 545,888.

To all whom 'it 'may concern: I

Be it known that I, JOHN K. STEWART, a citizen of thel United States, residing at Chicago, in the county of Cook and State of Illinoisl have invented newand useful Improvements in Motor-Cycle-Speed-Indicator Drive Connections, of which the following is a specification, reference being had to the accompanying drawings, forming a partthereo'f.

The purpose of this invention is to provide an improved connection for transmitting driving power to the speed indicator upon a motor cycle, adapted to prevent the inaccurate reading of the speedometer which is liable to be caused by the provision existing in the motor cycle for cushioning the steering wheel.

It consists in the features of construction shown and described as indicated in the claims.

In the dravfngsz-Figure 1 is a side elevation of the forward portion of a Amotor cycle having a speedometer equipped with this invention. Fig. 2 is a partly sectional elevation of the driving connection, section being made axially at the portion of the length containing the features embodying the invention. Figj?) is a detail section at the line 3-3 on Fig. 2.

The drawings represent a common construction of thevsteering member of ,a mot-or cycle comprising a resilient fork member, 1, at the lower end of which the steering wheel, 2, is journaled, and having mounted on the handle bar, in the customary position convenient for reading, a speedometer represented conventionally at 3, the driving power for operating the speedometer being transmitted from a gear, 4, on the steering wheel which-meshes with a pinion, 5, which is connected in any suitable manner with a lower end of a flexible shaft representedl in its entirety by the reference letter, A, and connected at the upper end with the speedometer.

In order to accommodate the relative change of position of the handle bar and the steering wheel axle due to the resiliency' of the fork member which is provided for cushioning the steering wheel in traveling over rough road or obstructions, the usual method of mounting the pinion, 5, is illustrated consisting in journaling it, with its connections to the flexible shaft, in a bearing, S, pivoted for swinging about the axis of the steering wheel and gear, 4, which drivesl said pinion, the pinion being positioned at the front or remy-#preferably at the rear, as illustrated,-of the gear, sothat the up-and-down movementwhich it receives in the up-and-down movement yof the handle bar relatively to the wheel causes it to traverse a limited arc whose chordis 'substantially parallel to the steering headaxis at the `side of the gear, 4, at which it is thus positioned. In traversing this arc, it is unavoidablel that thespeed of the pinion derived from the gear is increased in the downward movement and diminished in the upward movement, and that to this extent the speed indication. of the speedometer will be for the instant rendered iiiaccurategand since more or less of such up-and-down movement is constantly occurring in travelingy over an uneven road, the index needle of the indicator will bey constantly fluctuating, rendering it difficult for t-he rider to quickly read its indication, and also making that indication more or'less uncertain within a limited range. To adapt the iiexible shaft to accommodate this vertical movement and also to prevent the inaccuracy and uncertainty of indication resulting therefrom, as above explained, the lowest element, 10, of the rotary member of the flexible shaft which is directly connected to the gearing mounted in the bearing. S.,l is telescoped within the next member, 11, of said flexible shaft, and the two members, 10 and 11, are connected for transmitting power by a cio in, 12. in the lower member, 10, engaging a spiral slot, 13, in the.` upper member, 11. Both said members are included within thelower member, 14, of the casing, which, for a distance coveringthe entire extent ofl the' spiral slot and engagement therewith "ofl the cross-pin, is a piece of rigid tubing, the constructionbeing such as to dispense with flexibility ror the necessary distance. `'The direction of the spiral issuch as to counteract the rota- .tion of lthe shaft derived from the up-anddown movement of the pinion, 5. about'the gear, 4. When the pinion 1s mountedat the rear side of the gear, as illustrated, the slot llt) required .is a left-hand sp-ii'al --tliat is, has

the direction of the thread of a left-hand scr-ew, as illustrated.

Any convenient form of connection may be employed for transmission from the upper end of the spirally slotted member ll, with the speedometer. As illustrated, said member, ll, has a tlexibh shaft, 15, in t-he customary form of a closely wound spiral attached to its upper end and extending thence within. `the fiexible shaft casing, .16, to the upper end thereof for connection with vthe speedometer train. The upper portion of the flexible shaft above so much as is necessary to provide a aight way for the members, l() and itl, at their spiral slot conf neetious, s preferably flexible, as illustrated at i6, sail ilexible portion being coupled to the lower rid tabular portion by a cou pling, rlhe usual provision for connecting the easing of the vderible shaft at the upper end with the speedometer casing is employed, consisting of a coupling nut, 1S, having an interior flange, 18a, at its lower end which engages an exterior flange, 19a, of t-he terminal fitting, 19, of `the flexible shaft casing.

l. A speedometer driving connection comprising two members of a rotating shaft, one member having a spiral slot and 'the other member having a projection engaged therewith.

2. A speedometer driving connection comprising two members of a transmitting shaft, one telescoped within the other, the outer member having a spiral slot and the inner member having a pin engaging such slot.

la. speedometer driving connection'comprising a transmitting shaft, one end of which is adapted for connection with a speedometer, the other end being adapted for connection with rotating means, said transmitting shaft comprising two members which are connected with each otherw for rotation-by a spiral feature in one member, and a cooperating feature in the other memberengaging with the spiral, the pitch of the spiral being such as to permit easy longitudinal movement of the two members relatively to each other at their spiral en-l gagement by direct longitudinal thrust of the one toward the other, and means for maintaining said two members in axial alinementthroughout the range of their spiral engagement.

4. A speedometer driving connection com 'prisinga transmitting shaft, one end of which is adapted for connection with a speedometer, the other end being adapted for connection with rotating means, said transmitting shaft comprising two meinbers which are connected vwith each other for rotation by a, spiral feature in one member and a cooperating feature in the other member engaging with the spiral,

the pitch of the spiral being such as `to permit easy longitudinal movement of the two members relatively to each other atl their spiralengagement by direct longitie dinal thrust of the one toward the other, said members being telescoped with each other for maintaining them in axial alinement throughout the range of their spiral engagement.

5. A speedometer driving connection comprising a transmitting shaft, one end of which is adapted for connection with a speedometer, the other end being adapted for connection with rotating means, said transmitting shaft comprising two members which. are connected with each other for rotation by a spiral feature in one member and a Cooperating feature in tho other member engaging with the spiral, the pitch of the spiral beingsuch :is to permit easy longitudinal movement of the two mcn'ibers relatively to each other at their spiral engagement by direct longitudinal thrust .if the one toward the other, and a tubular casing in which said two members are inclosed throughout the range of their spiral engagement.

6. In combination with a motor cycle having a frame and a steering wheel mounted for up-and-down movement with respect thereto; a speedometer and driving connection therefor comprising a rotatable shaft composed of two members connected with each other for rotation by a spiral feature in one member and a cooperating feature in the other member `engaging with the spi nl; means connecting one of thex shaft members with the speedometer.; a driven wheel rigid with the other shaft member, a wheel and a journal therefor.' mounted for swinging about the axis of the steering wheel for transmitting rotation of the same to thc Asaid driven wheel, said journal being adapted to partake of the up-and-down movement of the frame.

7. In combination with a motor cycle having a frame and a steering wheel mounted for up-and-down movement with respect thereto; a speedometer and driving connection therefor lcomprising a rotatable shaft composed of two members connected. with each other for rotation by a spiral feature in one member and a cooperating feature in the other member engaging with the spiral, the pitch of the spiral being such as to per mit easyL longitudinal movement of the two members relatively to each other at their 'spiral engagement by direct longitudinal thrust of the one toward the other; means for maintainingv said two members in axial alinement throughout the range of their spiral engagement; means connecting one of said shaft members with the speedometer; a driven wheel rigid with the other shaft member, a Wheel and a journal therefor mounted for swinging about the axis of the steering Wheel for transmitting rotation of the same to the said driven wheel, saidl ythe other member engaging with the spiral; means connecting one of said shaft mem bers With the speedometer; means carried Concentrically about the axis of the steering Wheel for journaling one end of the other shaft member; connections carried there-by for transmitting the rotation of said steering Wheel to said shaft member, the journaling means being adapted to partake of the upl and-down movement of the frame.

. 49. n combination With a motor cycle hav ing a frame and a steering Wheel mounted for up-and--down movement with respect thereto; a speedometer and driving connections therefor comprising a. rotatable shaft composed of two members connected With eachother for rotation by a spiral feat-ure in one member and a cooperating :feature in the other member engaging with the spiral, the pitch of the spiral being such as to perA mit easy longitudinal movement of the two members relatively to each other at their spiral engagement by direct longitudinal thrust of the one toward the other, said members being' telescoped With each. other for maintaining them in axial alinement throughout the range of their spiral engagement; means connecting one ofthe shaft members with the speedometer', and means carried concentrically about the axis of the steering-Wheel for journaling one end of the other shaft member; connections carried f' thereby for transmitting rotation of said steering Wheel to said shaft member, the journaling means being adapted to partake of the up-and-down movement of the frame.

.10. In .combination With a motor cycle having a. frame and a steering Wheel mounted for up-and-down movement with respect thereto; a speedometer and driving connections therefor comprising a rotatable shaft composed of tWo members connected With each other for rotation by a spiral feature in one member anld avcoperating feature in the other member engaging with the spiral, the pitch of the spiral being such as to permit easy longitudinal movement of the tWo members relatively to each other at their spiral engagement by direct longitudinal thrust of thel one toward the other a tubular 'Casin "in which said two members are inclose throughout the rangev of their spiral engagement; means carried thereby .for

transmitting rotation of the steering Wheel to the shaft; a bracket secured to said casing .for keeping one end thereof concentric with the steering Wheel, said bracket beingadaptod to partake of the up-and-down movement of the frame.

ll. In combination. `with a mot-0r cycle having a frame, a steering Wheel' and links connecting it to the frame for up-and-down movement with respect thereto, a speedometer mounted on the frame and a drift/ing com nection therefor comprising a rotatable shaft composed of two members connected With each other 'for rotation by a spiral feature in one member and a cooperating feature in the other member engaging With the, spiral, one of said kraft members being connected 'With the speedometer, 'an arm pivoted for swinging vabout the anis of the steering Wheel, and rotatable connections carried by said arm for transmitting the rotation of said Wheel to the other shaft member, the said arm being longer than the aforesaid connecting links and being mounted for movement `with the same.

12. lIn combination with a. motorecyole having a wheehearrying fork, a Wheel journaled therein, a second fork and a frame carried thereby, means connecting the tivo forks at their upper ends adapted to permit their rela tive longitudinal movement, and a link connecting the lower ends of the forks,

a. speedometer mounted on the frame, and a driving connection therefor comprising a rotatable shaft composed of two members yconnected with each other for rotation by a spiral feature in one member and a copera-ting feat-ure in the. other member engaging with the spiral, one of said shaft members beingconnected with the speedometer, an arm pivoted for swinging about the axis of the motor-cycle Wheel, and rota-table connections carriedby said arm for transmitting the rotation of said Wheel. to the other shaft member, the said arm being longer than the fork-connecting llink and being mounted for movement with the same.

13. In combination with a motor-cycle having a Wheel-carrying fork, a wheel journaled therein, a frame and a second fork mounted therein, means connecting the tivo forks at their upper ends adapted to permit relative longitudinal movement of the forks; a link connecting the lower ends of the forks f and a speedometer mounted on the frame; a

tation by a spiral feature in one member and iso :l eoperuiing feature in the other member eugzru'ed with the spiral, the pieh of 'Lhe i spiral being,Y such :is to permi eue) ioug'iudh nul movement oi ihe two memhel ,relatively 'o eueh other at their Spirui engagement by direct 1ongitm'li-nnl thrust of J(he one toward the other, Suid members being ieleseoped with euch other for maintaining them in axial uliuement throughout the rango of their Spiral engagement, a teleseoping tubular Casing in which Suid two members) are n- In testimony whereof, I have hereunto set 15 my hand, at Chicago, Iliinois, this 8th day of February, A. D., 1910.

JOHN KERWIN STEWART.

VVitnes'ses:

J. V. FAIRFAX, W. M. MCARDLE. 

